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737 OHD Systems basic IRS logic

Somebody in another thread asked me about transplanting the IRS function from the 747 overhead logics to the 737 overhead logics.
Here’s what I did.First, in the 737 graphics, I converted the DispSource knob to be the IRSSelector1 knob by simply renaming it. I kept the old line as a remark for backup sake. Here’s what I added:
//element knob3,-184.8,-44.0,DispSource
element knob3,-184.8,-44.0,IRSSelector1
You may wanna additionally play with the “text” instructions around the knob and re-label them according to the three IRS knob positions (OFF – ALIGN – NAV), which have logic values of 0, 1 and 2.
Then, in the 737 logics:- in the [consts] section, I added one line for the timer duration:
irstimer = 1200
(where this value is equivalent to the standard 10 mins. of a full alignment cycle).
- in the [logics] section, I added these lines, grossly taken from the 747 Systems:if IRSSelector1=0 then
IRSAligned1=0
endif
if ((IRSSelector1=2) or (IRSSelector1=1)) then
IRSAligned1 = counter irstimer 2
endif
if (IRSSelector1=1) and (IRSAligned1 = irstimer) then
IRSAligned1=irstimer - 2
endif
if (IRSAligned1 >= irstimer) then
IRSNotAligned = 0
else
IRSNotAligned = 1
endif
Take it as it is, a basic inspiration; I am aware that this is not the full logic, and that it is based on a single IRS System, but it does anyway give you something to do about IRS when you’re setting up the cockpit before departure … any suggestion, correction, further development is absolutely welcome.

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Hi,

just to add my 2 cts worth idea: have you ever tried Thomas Richter´s very neat program called "Cockpit Systems B737" yet?
There you can find also the IRS part with offsets for the 2 kobs.
It´s really worth buying it. No messing around with offsets anymore as the entire overhead can be tested.